New computer worms use password trick
Password-protected attachments are the latest tactic virus writers are using to trick unsuspecting users into spreading computer worms.
Corporate email filters often block ordinary zipped attachments by default but may allow password-protected attachments through their defences. The trick is also designed to foil anti-virus software that can only unzip and check unlocked attachments. Furthermore, users may be more confident that a locked file comes from a trusted source and open it.
The most recent versions of the Bagle worm arrive in a compressed and password-locked .zip or .rar file. The password needed to unlock these attachments is included in the body of the email, and the recipient is urged to unlock the file as soon as possible.
Once the attachment has been unlocked and opened, however, the computer is infected and the worm is forwarded on to everyone in the victim's email address book.
